\subsection{Preflight checklist}

Before actual certification is commenced we perform a manual test using a 
checklist.
If any of the checks fail we immediately reject the product.
The checklist is given in the table below. All commands in \texttt{monospace}
are to be run in a terminal. Commands prefixed with a \texttt{\#} should be run
with root permissions. Commands prefixed with a \texttt{\$} should be run with
user permissions.

\begin{table}[H]
\begin{tabularx}{\linewidth}{|l|X|}
	\hline
	Check 1 & Get the SUT in a workable state. \\
	\hline
	Course of action &
		\begin{enumerate}
			\item Import the VirtualBox image into VirtualBox.
			\item Boot the vm.
			\item Verify the SUT booted successfully and the network modules
				are loaded.
		\end{enumerate}\\
	\hline Passed & \textit{Yes/No} \\
	\hline\hline
	Check 2 & Verify the SUT is complete. \\\hline
	Course of action &
		\begin{enumerate}
			\item Boot the SUT as in \emph{Check 1}.
			\item Verify the loopback device exists by running
				\texttt{\$ ifconfig}.
			\item Verify the \emph{echo-server} is present on the system.
			\item Verify \emph{Scapy} is present on the system by running
				\texttt{\$ scapy}.
			\item Verify all scripts used for testing are present on the
				system.
		\end{enumerate}\\
	\hline
	Passed & \textit{Yes/No}\\
	\hline \hline
	Check 3 & Initialize the testing environment.\\
	\hline
	Course of action &
			\begin{enumerate}
				\item Boot the SUT as in \emph{Check 1}.
				\item Setup iptables by executing 
					\texttt{\# code/iptables.sh}~\footnote{ The IPTables script
					ensures that the OS does not drop packets due to an the
					unknown source.}
				\item Navigate to the working directory by running
					\texttt{\$ cd /home/student/tt2015}
				\item Compile the echo server by running 
					\texttt{\# cd code/server \&\& make \&\& cd -}
				\item Start the echo server by running
					\texttt{\# cd code/server \&\& java Main}
		\end{enumerate}\\
	\hline
	Passed & \textit{Yes/No}\\
	\hline\hline
	Check 4 & Test the tool environment.\\
	\hline
	Course of action &
		\begin{enumerate}
			\item Initialize the SUT as in \emph{Check 3}
			\item Execute the test script by running
				\texttt{\# code/client/helloworld.py}.
			\item Verify the console displays a success message.
		\end{enumerate}\\
	\hline
	Passed & \textit{Yes/No}\\
	\hline\hline
	Check 5 & All test inputs and scripts are present. \\\hline
	% DIT MOET NOG EVEN ANDERS
	Course of action & 
		\begin{enumerate}
			\item Boot the SUT as in \emph{Check 1}.
			\item Execute the command \texttt{ls scripts/tests}
			\item Verify that there is a file named case$X$ for each test case $X$
			\item Use \emph{ls packets}
			\item Verify that there is a file named \texttt{single.pcap} and
			\texttt{multi.pcap}.
		\end{enumerate}\\
	\hline
	Passed & \textit{Yes/No}\\
	\hline
\end{tabularx}
\end{table}

\newpage

\subsection{Testing of SUT}
The SUT is a series of services for other computer programs with no end-user
facing interface. Therefore the SUT will be tested solely by calling it's
services through various automated scripts. An automated test suite will be
available which executes all these automated scripts and aggregates their
results to asses whether or not the SUT has passed the test. 

The implementation of the SUT is tested using black box testing techniques. A
series of tests asses the correctness of the implementation with regards to the
TCP specification. These tests are specified in Table~\textbf{referentie naar
tests-tabel}. The test cases aim to cover the most interesting parts of the TCP
specification. 

To cover the TCP specification as complete as possible while still maintaining
a feasible test suite the tests are divided into equivalence partitions. Below
these partitions are given.

\begin{enumerate}
	\item \emph{Number of packets} in request~\footnote{A request is considered
		establishing a connection (handshake) and a number of payload packets}
		\begin{enumerate}
			\item 0 payload packets
			\item 1 payload packet
			\item n=small payload packets
			\item n=big payload packets
		\end{enumerate}
	\item Correct or incorrect \emph{source port}
	\item Correct or incorrect \emph{destination port}
	\item Bits flipped in \emph{payload}
		\begin{enumerate}
			\item Correct payload
			\item Payload with even number of bits flipped
			\item Payload with odd number of bits flipped
		\end{enumerate}
	\item Correct or Incorrect \emph{checksum}
	\item Packets received in or out of order, or missing packets
\end{enumerate}

\textbf{hier iets over waarom deze partities relevant zijn! Waarom odd en 
even number of bits flipped bijv interessant?}
\bigskip

Partitions 2 to 6 are tested using pairwise testing to keep the number of test
cases feasible. The pairs are then all *except some where it does not make sense
to do so) tested with the different request sizes of partition 1.

This is expressed in Table~\ref{table:testpairs}.

\begin{table}
% DIT MAAK IK NOG EVEN MOOI
	\begin{tabularx}{\linewidth}{p{2cm} | l | p{2cm} | l | p{1cm} || c | c | p{1.3cm} | p{1.3cm}}
	\textbf{Payload}      & \textbf{checksum}  & \textbf{destination port} & \textbf{order}         & \textbf{source port} & \textbf{payload 0} & \textbf{payload 1} & \textbf{payload small} & \textbf{payload big} \\  \hline \hline
	Correct               & Correct   & Correct          & In order       & Correct     & \checkmark & \checkmark & \checkmark & \checkmark \\  \hline
	Correct               & Incorrect & Incorrect        & Missing packet & Incorrect   & \xmark & \xmark & \checkmark & \checkmark \\  \hline
	odd\# of bits flipped  & Correct   & Incorrect        & Out of order   & Incorrect   & \xmark & \xmark & \checkmark & \checkmark \\  \hline
	odd\# of bits flipped  & Incorrect & Correct          & Missing packet & Correct     & \xmark & \xmark & \checkmark & \checkmark \\  \hline
	even\# of bits flipped & Correct   & Incorrect        & Missing packet & Correct     & \xmark & \xmark & \checkmark & \checkmark \\  \hline
	even\# of bits flipped & Incorrect & Correct          & Out of order   & Incorrect   & \xmark & \xmark & \checkmark & \checkmark \\  \hline
	odd\# of bits flipped  & Incorrect & Incorrect        & In order       & Incorrect   & \checkmark & \checkmark & \checkmark & \checkmark \\  \hline
	even\# of bits flipped & Incorrect & Incorrect        & In order       & Incorrect   & \checkmark & \checkmark & \checkmark & \checkmark \\  \hline
	Correct               & Incorrect & Incorrect        & Out of order   & Correct     & \xmark & \xmark & \checkmark & \checkmark \\  
\end{tabularx}
\caption{Combinations of test cases}
\label{table:testpairs}
\end{table}

\subsection{Quality, completeness and coverage of tests}

The network packets used in testing are constructed from prerecorded, known to
be correct, network traffic. These packets are then modified with well used and 
field tested tools. Due to this the chance of errors in the test cases is quite
low. However, no formal proof of correctness of the test cases is present, this
means that any defects found might not be the result of a fault in the SUT.
Therefore detected defects should only indicate there is a high chance that 
there is a fault in the SUT and can not result directly in the conclusion that
there actually is one. 

\bigskip

Due to the nature of black-box testing coverage of the code in the 
implementation of the SUT is unknown. However completeness of the tests over 
the specification of the SUT can be assessed. 

\bigskip

Due to the clear and exhaustive specification of TCP the completeness of the 
test suite can be clearly assessed. 

As always, $100\%$ completeness is not feasible, therefore test cases are
carefully selected to cover the most interesting parts of the TCP specification
to ensure a test suite.

To further decrease the number of tests needed test cases are divided into
equivalence partitions and the combination of cases as described in 
Table~\ref{table:testpairs} ensures that all partitions are
covered and the number of individual tests is still feasible. 


%
% wat ik ook probeer ik krijg de eerste collum
% zijn tekst niet verticaal gecentered
%


\subsection{Test cases}

%\begin{table}
%\begin{tabularx}{\linewidth}{| l | X|}
%\hline
%Nr & 1 \\\hline
%Title & Single valid request. \\\hline
%Input & Pcap file with prerecorded valid packets. \\\hline
%Expected output & Pcap file with valid response to request. \\\hline
%Course of action & \begin{enumerate}
%	\item Execute \emph{./scripts/tests/case1-single-valid.sh}
%	\item Load \emph{output/case1.pcap} with ...
%\end{enumerate} \\\hline
%Valid trace & \begin{enumerate}
%	\item \textbf{Hier packets benoemen?}
%\end{enumerate} \\\hline
%\end{tabularx}
%
%\begin{tabularx}{\linewidth}{| l | X|}
%	\hline
%	Nr & 2 \\\hline
%Title & Single request with corrupted checksum. \\\hline
%	Input & Pcap file used as \emph{test-case 1} input. \\\hline
%	Expected output & No response from SUT, logs with rejected packets. \\\hline
%	Course of action & \begin{enumerate}
%		\item Load input pcap file into ....
%		\item Corrupt checksum of loaded packets.
%		\item Save resulting packets as pcap file.
%		\item Load new pcap file into ...
%		\item Replay new pcap file.
%		\item Record SUT response using...
%		\item Extract log with rejected packets.
%		\item Save recorded packets as a pcap file.
%		\item Analyze packets in resulting file.
%	\end{enumerate} \\\hline
%	Valid trace & \begin{enumerate}
%		\item \textbf{Aangeven welke packets corrupted zijn?}
%	\end{enumerate} \\\hline
%\end{tabularx}
%\end{table}

\newpage
